3D objects with laser cutter

Most of us know of laser cutting, same routine:

1. You design a 2D drawing of the cuts you need and save it.
2. You go to the nearest laser cutter and put a material on the plate.
3. You insert your design and operate the machine.
4. You get the parts out from the plate that look like this –                 (* Yes, I know that steps 2,3,4 can be skipped by services as Ponoko)

Smart people from Hasso Plattner institute found a way to use regular laser cutter to manufacture 3D objects. as can be seen here:

you can see details here.